Both aircraft were flying under supervision of Swiss air traffic control. Peter Nielsen, the only air traffic controller on duty at the time, gave the Bashkirian Airlines flight warning that it was dangerously approaching the DHL cargo craft. With a mere 44 seconds to spare, and following Nielsens's directions, the Russian aircraft descended directly into the path of the freighter. At around 11:43pm local time, the two airplanes collided in mid-air, and 71 persons perished.

Mr. Nielsen had wrongly instructed the Bashkirian Airlines plane to descend, even though its onboard warning equipment told it to climb. His colleague had taken an unauthorized break, leaving Mr. Nielsen with a heavy workload and two air traffic control stations to monitor. But whether or not this collision was a result of faulty air traffic control is not the purpose of this post.

Here is where it gets interesting: Vitaly Kaloyev, a Russian architect whose family was onboard the doomed Bashkirian Airlines flight 2937, took matters into his own hands and murdered the Swiss air traffic controller on duty at the time of the accident.

Vitali Kaloyev with his daughter Diana, who was killed in the crash. Kaloyev participated in the wreckage search for the bodies and located his own daughter's corpse.

According to investigators, on February 21 Vitali Kaloyev arrived in Zurich and checked in to the Welcome-Inn in the suburb of Kloten. The hotel is not far from where Peter Nielsen, the 36-year-old Danish air traffic controller widely blamed for the 2002 crash, lived with his wife and three children.

On the afternoon of February 24, he set off for Mr Nielsen's house. A neighbour spotted Mr Kaloyev and asked what he wanted. He waved a piece of paper with Mr Nielsen's name on it. The neighbour pointed to Mr Nielsen's front door, but instead of knocking, Mr Kaloyev sat down in the garden.

Mr Nielsen, who had lived in Switzerland since 1995, spotted the intruder, went outside and asked what he wanted. Swiss detectives say his children went into the garden as well; his wife called them back, and was still inside when she heard a "kind of scream". She rushed out to discover her husband in a pool of blood.

Yesterday Mr. Kaloyev, the Russian architect, was sentenced to eight years in a Swiss prison for the premeditated homicide of Peter Nielsen, the Swiss air traffic controller.

Also important to note that one pilot listened to the air traffic controller and the other pilot listened to the collison-avoidance system (both descended). Had both listened to the air traffic controller, the collison may have been avoided.

You cant blame Peter Neilsen... He didnt have the proper equipment to avoid the crash and he tried to the conflict between his command and the TCAS made the situation much worse...And 8 years in prison isn't enough!! That guy is a murderer!!